چکیده انگلیسی

Recently, it has been reported that United Arab Emirates is considered one of the highest energy consumers per capita in the world. Consequently, environmental pollution and carbon emission has been a major challenge facing the country over the past several years due to unprecedented high economic growth rate and abnormal population increase. Utilization of hydrogen energy to fulfill UAE’s energy needs would be one of the key measures that the country could undertake to achieve a sustainable development and without any major environmental consequences. Hydrogen energy, which is an energy carrier, is consider by many scientists and researchers a major player in fulfilling the global energy demand due to its attractive features such as being environmentally clean, storable, transportable and inexhaustible. It can be used as a fuel in the proton exchange membrane (PEM) fuel cell, which is an electrochemical device that generates electric power and it can be utilized in various applications. Production of hydrogen energy can be carried out either through utilizing conventional resources or by renewable resources. Conventional resources such as crude oil and natural gas can produce hydrogen by steam-reformation while hydrogen can be produced from coal through gasification. On the other hand, hydrogen production through renewable resources can be achieved through biomass gasification, solar-hydrogen, wind-hydrogen and hydropower electrolysis process. Other renewable resources such as geothermal, wave, tidal and ocean thermal energy conversion (OTEC) can also contribute into hydrogen production but at a marginal level. In this report, a roadmap to achieve a sustainable development in the UAE through utilization of hydrogen energy is presented. The report highlights the potentials of energy resources that the country possesses with respect to both conventional and non-conventional energy and determines major resources that could significantly contribute to production of hydrogen energy. Moreover, the study will present three proposals where PEM fuel cells are introduced in the country’s electricity, transportation and commercial sectors to fulfill its energy demand and achieve the desired sustainability as well as environmental and economical benefits associated with such schemes compared with business as usual.

مقدمه انگلیسی

Since its independence in 1971, United Arab Emirates (UAE) took huge steps toward achieving a solid and sustainable economic growth as well as urban development. Subsequently, the population of the country has risen tremendously because of high urbanization and increase in the number of expatriates that are residing and working in various sectors throughout the country. Currently, the UAE with a total area of 84,000 km2 has one of the most diversified economies of all the major oil-producing Arabian Gulf states. The economic diversification was carried out through implementation of several major projects in various sectors, including refinery and petrochemicals, tourism, banking, real estate, aviation and airports, re-export commerce, and telecommunications making the UAE to be the second largest economy in the Middle East. For instance, Dubai, which is one of the key emirates in the country has become a central hub for regional trade and finance, accounting for about 70% of the emirates’ non-oil trade in 1998 [1]. Furthermore, free trade zones are established in all major emirates in order to provide a significant contribution to the gross domestic product (GDP).
According to Energy Information Administration (EIA), UAE’s maximum crude oil production capacity is estimated to be around 2.5 million barrels per day (bbl/d). In addition, the country’s natural gas production is estimated to be approximately 4 billion cubic feet per day (bcf/d). Generally, UAE plays an essential role in the world energy market because it possesses roughly 100 billion barrels of proven oil reserves, which is nearly 10% of the world’s crude oil supply. Moreover, UAE possesses about 215 trillion cubic feet of natural gas, which is regarded the world’s fifth-largest natural gas reserves after Russia, Iran, Qatar and Saudi Arabia [2].
With high economic and population growth rates and a fairly low energy cost, the country’s energy consumption has risen tremendously in the past decades, making it one of the highest energy consumers per capita in the world. Consequently, environmental pollution and carbon emission has reached a record high. For instance, UAE’s emission per capita was at least twice of the developed countries such as the United States and EU countries with an annual average emission of 10.5 tonnes carbon equivalent (TCE) per capita in the past 23 years period. Surprisingly, the world’s annual average emission was at a marginal rate of 1.1 TCE per capita during the same period [3].
Many scientists, energy economists, and energy policy makers believe that hydrogen energy, which possesses significant attractive characteristics such as being environmentally clean, storable, transportable and inexhaustible, could play a key role in UAE’s future sustainable development by meeting the country’s future energy demand and without any environmental sacrifices. Hydrogen can be produced from either conventional energy resources (oil, natural gas and coal) or non-conventional energy resources such as nuclear, biomass, solar, wind energy, hydro energy and other renewable resources.
Hydrogen can be used in both liquid and gaseous forms. This energy carrier can be used to fuel a revolutionary device named proton exchange membrane fuel cell (PEM), used in major applications throughout the world. PEM fuel cell presented in Fig. 1 is a device that utilizes hydrogen as a fuel and oxygen to generate electricity through an electrochemical process and producing heat and water during the operation. A single fuel cell has no significant meaning due to its low power output. Therefore, several fuel cells are arranged in a stack to provide the desired electrical power. Presently, PEM fuel cells have demonstrated to gain worldwide attention due to their attractive characteristics such as being environmentally clean, low operating temperatures and achieve a quick response. Generally, this type of energy converter is used in transportation; stationary power for residential and commercial proposes and recently fuel cells are considered for aerospace applications [4].Theoretically, a PEM fuel cell operates at any temperature ranging from 0 °C to 100 °C, although in practice this range is from 10 °C to 80 °C. The fuel cell’s performance, which is described in terms of cell voltage and power density, is usually better at an elevated temperature due to a higher reversible voltage and a lower ohmic resistance, but activation and concentration overpotentials are somewhat higher [5]. Fuel cell’s performance can be greatly improved if pure oxygen is utilized instead of a dry air, where oxygen accounts only 21% by volume. In other words, oxygen’s partial pressure is about 5 times higher than oxygen in air, so that it causes a significant reduction in the overall electrochemical potential. Therefore, the performance curves of a fuel cell operating on air as an oxidant are different from the one operating on oxygen [6].
The objective of this report is to present a roadmap to achieve a sustainable development in the UAE through hydrogen energy. The report will highlight the potential of UAE’s energy sources that possesses in terms of conventional and non-conventional energy resources and through which hydrogen could be produced and to determine major resources that could significantly contribute to production of hydrogen energy. Moreover, economical and environmental assessment of introducing hydrogen fueled PEM fuel cell in country’s three major sectors namely commercial, power generation and transportation sectors are to be carried out as well.

نتیجه گیری انگلیسی

In this report, a roadmap to achieve a sustainable development in the UAE through hydrogen energy was presented. The report highlighted the potential of country’s energy sources that possesses in terms of conventional and non-conventional energy resources for producing hydrogen energy. In addition, the report proposed utilization of hydrogen fueled PEM fuel cell in three major sectors namely commercial, power generation and transportation sectors to fulfill the country’s energy demand and achieve the desired sustainability as well as environmental and economical benefits associated with such schemes compared with business as usual. The conclusions are summarized as follows:
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The UAE has huge reserves of fossil fuel such as crude oil and natural gas, and possesses a significant renewable resource of solar energy and biomass energy with slightly lower intensity of wind energy. Conversely, other renewable resources exist but at a lower intensity and with exception to Hydropower, which the country lacks.
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Natural gas steam-reformation process is considered the best candidate for hydrogen production among other fossil fuels due to its low carbon emissions and cost effectiveness. In addition, it was demonstrated that the higher the utilization percentage of natural gas, the more cost effective hydrogen would be produced and stored.
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Solar energy could play a major role in the UAE energy sector in the future since it has a great potential of solar energy with average solar insolation exceeding 8.5 GJ/m2 year, which could be used to generate electricity through photovoltaic cells and produce hydrogen through electrolysis process.
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Wind energy potential in the UAE is considered to be on the low side with city of Al Ain demonstrated to have the highest wind power distribution among other cities in the country. Nevertheless, the generated wind power could be utilized for small-scale applications and pumping water for irrigation.
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A significant potential of hydrogen production can be realized in the UAE through its agricultural residues making up to 10% of the total agricultural land with an average annual biomass production of 15 dry tones per hectare.
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Cost of hydrogen produced by natural gas steam-reforming is slightly more attractive than hydrogen produced by biomass gasification. However, total cost of solar-hydrogen and wind-hydrogen are considered far higher than other hydrogen energy producing methods, even though they do not contribute any carbon emission.
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The report illustrated the significance of introducing hydrogen fueled PEM fuel cell in three key sectors in the country and through which major economical and environmental savings could be achieved if such plans are implemented. However, it should be emphasized that the sooner the hydrogen energy is introduced to the UAE’s energy consuming sectors, the greater the benefits will be gained.